Table 1.

Bacterial strains evaluated and the ΔRQ values generated in PCR with the Pr2a and Pr2c primers and the Yer-prb fluorogenic probe

Bacterium evaluatedΔRQ valueaInterpretationb
Y. enterocolitica (virulent serotypes)
 O:3c29.26Positive
 O:9c29.95Positive
 O:8c29.65Positive
 O:18c29.56Positive
 O:20c29.13Positive
 O:21c29.38Positive
 O:13c29.39Positive
Y. enterocolitica (avirulent serotypes)
 O:22c3.36Negative
 O:22d3.19Negative
 O:7c2.89Negative
 O:7e3.26Negative
 O:10d3.05Negative
 O:10e3.20Negative
 O:34e3.33Negative
Other species of Yersinia
Y. aldovaec2.24Negative
 Y. bercovieric2.05Negative
 Y. frederikseniic2.67Negative
 Y. intermediaic2.71Negative
 Y. kristenseniic1.93Negative
 Y. mollarettic2.29Negative
 Y. pseudotuberculosisf1.85Negative
 Y. ruckeric2.82Negative
Other bacteria
 Citrobacter freudiniif2.24Negative
 E. colig1.26Negative
 E. coliO157:H7g1.49Negative
 Flavobacterium spp.g1.24Negative
 Salmonella enterica serotype chloleraesiusg0.81Negative
 S. enterica serotype Typhimuriumg1.54Negative
  • a Determined with ∼107CFU/ml for each strain.

  • b A positive score is assigned when the ΔRQ is greater than the ΔRQ threshold, based on a fourfold average value of the no-template controls.

  • c From the National Animal Disease Center, United States Department of Agriculture. Ames, Iowa.

  • d From the Centers for Disease Control and Prevention, Atlanta, Ga.

  • e From the Food Microbiology Culture Collection, Kansas State University, Manhattan.

  • f From M. M. Chengappa, Veterinary Diagnostic Laboratory, Kansas State University.

  • g From R. D. Oberst, Food Animal Health and Management Center, Kansas State University.